Loft leaves open hole

 From:  Michael Gibson
2157.4 In reply to 2157.3 
Hi Leonard, just got your e-mail and replied, sorry I didn't look close enough to notice the hole in your new post here, I just thought that was a "Work in progress" update at first!

It can be hard to do a bowl with a kind of "topographic" style arrangement like you've got there, normally I would think more of doing vertical profiles for it (similar to what I posted earlier in this thread) instead.

One way to close off what you have in this case is to select that innermost little profile and run Construct/Planar to build a planar surface from its outline. Then zoom in until you can select that little planar surface, then select it and your larger one, and run Edit/Join and then you will have sealed off that little hole. It looks like you may have already thickened that surface into a solid with some "side walls" in it, if so then you want to delete the little side wall pieces so that you can instead join the small end cap to the bottom, the small caps will not join to the other pieces unless their edges are open and not attached to an existing surface which is why you want to delete the small vertical side wall part.

If you do want to do profiles in that direction as you have here, it can sometimes be a good idea to try and build your shape in a couple of pieces (each of which is more simplified and uses fewer profiles) and rely on filleting to smooth it out, rather than trying to build everything all in just one single surface command like Loft or Sweep.

The more profiles you add to a Loft will tend to "over constrain" it and tends to introduce undulations and wiggles in the surface unless you have things placed at very optimal locations.

Here is a method to illustrate - instead of trying to make a whole bowl in one go, I just focus first on the side parts, and intentionally let the bottom come to a sharp drop:

Now I draw some new profiles and use them to sweep a separate surface for the rounded bottom portion of the bowl:

Now these surfaces can be trimmed to one another and the excess parts discarded, then use Edit/Join to glue them together and then fillet the common edge:

The 3DM model for the above images is attached here as .

The benefit to this approach is that you get to focus more on some individual elements of the shape rather than having to do the whole thing all in one go, then let fillet do some of the work to fill in a rounded part to connect things up.

Hope this helps!

- Michael